All incidents recorded a "casualty", but the few "fatalities" are marked with a big flag. In most cases, I would assume the fatality (or casualty) was the person on the bicycle, except perhaps in motorcycle vs bike where it could be the faster-moving vehicle. Unfortunately the data does not assign casualties to vehicles (well, not obviously) but again, it's very probable that if there were casualties, one of them was the person on the bike.

Sometimes it is hard to concentrate on the data analysis, and try not to imagine what each of those little flags actually mean...